An apparatus is known in which an electric igniter is combined with a piston, and the piston is caused to move in a predetermined direction as a result of receiving a pressure created by combustion products generated by the actuation of the electric igniter (or a combination of the electric igniter with an explosive component).
EP-A No. 0965483 discloses an invention relating to a delay device for an explosive charge.
FIG. 1 depicts a device in which an electric igniter, two pistons, and a hydraulic oil are accommodated in a housing, and FIG. 2 depicts a device in which an electric igniter, a spring, and a single piston are accommodated in a housing.
It is indicated that the device depicted in FIG. 1 operates in the following manner.
Where an electric igniter 1 is actuated, a charge 2 is ignited and generates a gas. As a result of receiving the pressure of the gas, a first piston 5 moves in the axial direction inside a first cylinder 4. A hydraulic oil 10 is pushed by the movement of the first piston 5 and into a flow channel 6.
Since the flow channel 6 is connected to a second cylinder 8, a second piston 9 is moved in the axial direction inside the second cylinder 8 by the hydraulic oil pushed into the flow channel 6.
Since the second piston 9 has a cross-sectional area larger than that of the first piston 5, the movement speed of the second piston 9 is less than that of the first piston 5.
The delay device for an explosive charge disclosed in EP-A No. 0965483 uses the delay operation such as described hereinabove to change the inclination of a neck support provided at a seat of an automobile.